Azo dyes



Patented Jan. 28, 1941 UNITED STATES PATENT OFFICE AZO DYES Frithjof Zwilgmeyer, Wilmington, DeL, assignor to E. I. du Pont de Nemours & Company, Wilnington, Del., a corporation of Delaware 1 No Drawing. Application June13, 1939,

Serial No. 278,847

2 Claims. (Cl. 260-186) A. This invention relates to new dyes, to mixhue o organic m oun s s i ble for he pr du on o es. an particularly o c ors hi h are developed on the fiber. Specifically, it relates o dyes formed b h com inat n of di ot 2z5 alko s nilin it u lin compo n suitable for the production oi water-insoluble colors, particularly with coupling components such as the aryl-amides of 2:3-hydroxy-naphthoic and beta-keto-carboxylic acid. This is a continuation in part of the application identified as Zwilgmeyer, Serial No.'15'3,523, filed July 14,

1937 and now abandoned.

B. E. I. du Pont de Nemours and Company holds a patent covering dyes obtained by coupling aryl-diazo compounds to naryl-azo-lacetyl-amino-l-naphthol. However, the combination of diazotized .2:5-.diall;oxy-aniline with those componentsis not specifically disclosed.

C. I have discovered that the combination of 2:5-dialkoxy-ani1ine with the aforementioned types of coupling components produces a color having particularly valuable properties. Ran ticularly [valuable are the colors having the formulas:

O CH:

N=N NO: may MG on.

O OH: OH

! OHaCOHN N=NGNm l. he o t v lu b e ob e t o t i inv n re a ta ne by co lin d zo o -d meth yw n line th i-o l-a o-1 a e m o- -nap tho n s b tan e o n the b b n of the var u me h d k n t the a Those dyes are r ferabl l e o fiber y intin h re n a th ckened so ution re a ed f om a om osition comp i a dia o-im no de i ati e '5 d1 ni inc and th c u ling c m ponent i a pro ima el oquimoloou 'or p opon:

tions and developing the color by after-treatment of the printed material with acid fumes. The dyeings so obtained possess exceptional fastness properties, particularly to washing and light.

E. This invention is more completely understood by reference to the following examples, which are illustrative and not limitative of the invention, All quantities are given in parts by weight.

Example I A printing paste was prepared as follows: 1.7 parts of a diazoirnino compound of the formula:

OCHa l CgHiOH prepared 'by' reaction of diazotized 2:5-dimethoxy-aniline with diethanolamine;

2.3 parts of 4-(3-nit ro-phenyl-'azo)-l-acetyl amino-'l-naphthol of the formula:

NH 0 CH:

and obtained by coupling diazotized m-nitroaniline with 1:7-amino-naphthol under acid conditions followed by acetylation;

Cotton and rayon piece goods were printed, by means of an engraved roller, with the above paste. The printed fabric was air dried and then subjected to the action of live steam containing acetic acid vapors in the conventional acid ager.

' Color development occurred during this process and the dyed fabrics then were rinsed, soaped and again rinsed and dried. A deep reddish brown shade of exceptionally good fastness to washing and light was obtained. The dyehas the following formula:

OCH:

Example II I i I I A printing paste was prepared accordingto the 1 formula of Example I, except that 4- (4'-nitro -2"-; methoxy-phenyl-azo) -1-acetyl-am.ino 7 naph thol was substituted for the 4-(3'-nitro-phenylazo)- derivative. This coupling component has the structure NHCOCH:

OCH;

OCHa

Example III A printing paste comprising; the following: 2 parts of a diazoimino compound of the, formula:

OCH;

CHPCH! OH: I

OCH;

prepared by the reaction of diazbtizedZzS-dir methoxy aniline with piperidlne-alpha-carboxylic acid; 2 parts of a coupling componentrof the formula:

omconN N=N I Parts Mono-ethyl ether of ethylene glycol 4 Water! 24 30% sodium hydroxide solution 3 Starch-tragacanth thickener 65 Cotton piece goods were printed with the above paste and the color developed by treating the printed material with steam and acid fumes. A deep blackish brown dyeing of excellent fastness properties was obtained. 1

ExwmpZeIV A printing paste was prepared by the formula given in Example III except that a diazoimino- I OCH;

prepared by the reaction of diazotized 2-5-dimethoxy-aniline with methyl "glucamine'; was piperidine alpha-carboxylic substituted for the acidderivative. I

This composition was printed'on cotton-fabric and the color developed as in Example III. The

dyeing obtained was'identical with that ores-- ample III. t Y' 7 Example V A printing paste was prepared'by the formula, given in Example 1H,,except that a-coupling component of the formulae v y was substituted for, the coupling component.

that example.

Cotton material was printed and the colorllefl. veloped as in Example III. A dark brown dyeing" of excellent fastness properties was obtained.

Example VI A printing paste was prepared as in Example I only using the diazoimino compound of the formula: g A

0 Cam 0 OzHt F. The above examples are illustrative of methods of applying these dyes. They find '-their most important use in printing where the stabilized diazo component in mixturewith the;

pound. Obviously these color combinations can be prepared in substanceas well as on the fiber in which case they may be utilized as pigments or they may be temporarily solubilized, applied to the fiber, and de'solubilized thereon. Otheri coupling component is printed on thefiber and developed by hydrolysis of the diazoimino comalkoxy amines in addition to those disclosed can be used.

G. According to this invention new azoic colors of exceptional shades and fastness properties I claim: 1. The compound represented by the formula:

I N===N no, 5

onioonN N=N- I OCH: 10

2. Fibers dyed with the compound of claim 1.

FRITI-IJOF ZWILGMEYER. 

